Ice making machines, or ice makers, typically comprise a refrigeration and water system that employs a source of refrigerant flowing serially through a compressor, a condenser, a thermal expansion device, an evaporator, and a freeze plate comprising a lattice-type cube mold thermally coupled with the evaporator. Additionally, typical ice makers employ gravity water flow and ice harvest systems that are well known and in extensive use. Ice makers having such a refrigeration and water systems are often disposed on top of ice storage bins, where ice that has been harvested is stored until it is needed. Such ice makers may also be of the “self-contained” type wherein the ice maker and ice storage bin are a single unit. Such ice makers have received wide acceptance and are particularly desirable for commercial installations such as restaurants, bars, motels and various beverage retailers having a high and continuous demand for fresh ice.
In these ice makers, water is supplied at the top of a freeze plate which directs the water in a tortuous path toward a water pump. A portion of the supplied water collects on the freeze plate, freezes into ice and is identified as sufficiently frozen by suitable means whereupon the freeze plate is defrosted such that the ice is slightly melted and discharged or harvested therefrom into an ice storage bin. Typically, these ice machines can be classified according to the type of ice they make. One such type is a grid style ice maker which makes generally square ice cubes that form within individual grids of the freeze plate which then form into a continuous sheet of ice cubes as the thickness of the ice increases beyond that of the freeze plate. After harvesting, the sheet of ice cubes will break into individual cubes as they fall into the ice storage bin. Another type of ice maker is an individual ice cube maker which makes generally square ice cubes that form within individual grids of the freeze plate which do not form into a continuous sheet of ice cubes. Therefore, upon harvest individual ice cubes fall from the freeze plate and into the ice storage bin. Control means are provided to control the operation of the ice maker to ensure a constant supply of ice. Various embodiments of the invention can be adapted to either type of ice maker, and to others not identified, without departing from the scope of the invention.